"Zombie Wolf" wrote in message
...
Make a Half - wave vertical with pipe. If the wall is dry wood, you can
simply clamp it in place on the wall. You figure out the length of this
antenna by the following formula

468 / freq (in MHZ)

Hook the center conductor of the coax to the antenna, and then simply run
a wire from the shield braid of the coax to a nearby ground. Presto. You
now have a half - wave vertical.

The end impedance of a half wave antenna is in the neighborhood of
1000--5000 Ohms depending on the diameter of the conductor; fatter
conductors, lower Z.

Connecting a coaxial cable to the bottom end of a half wave element and the
shield to ground will then result in a V.S.W.R. of roughly 2500/50 or
500:1. You need to convert the feed Z to 5o Ohms either by:

1. A quarter wave stub as in the popular J antenna
2. A lumped element L or Pi network


Dale W4OP